The present invention relates to carbon dioxide absorption devices used in breathing assistance systems and more particularly to recirculatory aided respiration systems for surgical or other medical applications, usually involving anesthesia.
In using recirculating breathing assistance systems, particularly with patients who are experiencing breathing difficulty because of trauma, surgical procedures, anesthesia, or other reasons, it is generally desirable to provide heated and humidified air to the patient. Warm, humidified air prevents "drying out" of the mucocilliary tissues of the patient's respiratory system, and reduces patient heat loss that results from evaporation of water vapor from the lungs. It is also desirable that the air provided to the patient be relatively free of any contamination, especially contamination which may result from previous use of the system by another patient.
Complicated, proven hazardous, and relatively expensive apparatus have often, been employed to condition the air supplied to a patient in a recirculatory aided respiration system. Where such a system is in use for a surgery or other operating room procedure, anesthesia gases or other conditioning agents are often introduced into the stream of air inhaled by the patient. Also, any recirculation system requires the removal of carbon dioxide from the air exhaled by the patient.
Such prior art systems for warming and humidifying air supplied to a patient often require the use of water reservoirs, heaters, and complicated delivery systems including complex electrical/electronic controls. Those systems may require complex hose connections and knowledge of the control systems; they may also require a significant amount of space in the operating room. Setup of these prior art systems can be quite complicated, and the systems may require substantial capital outlay as well as costly supplies. In such previous applications, the use of heated humidifiers is prevalent in order to provide proper conditioning for the air and entrained gases supplied to the patient.